A teacher uses reflections, analysis, and study of her own teaching and learning across a 23-year period to consider a case of science knowledge development. Because her learning about science has become increasingly influenced by analyses of her own students learning, the teacher's pedagogical autobiography is interwoven with stories of her students' changing understandings of science, focusing particularly on a case study of one student's learning about science across a year. The report concludes with a discussion of implications of the autobiographical journey. Conditions that supported the teacher's growth are used to consider ways of supporting prospective and practicing teachers' education and development in two areas: development across time of increasingly complex and rich knowledge about what it means to understand science and development of an inquiring, reflective, and analytical stance towards learning from science. (Author/PR)